defmodule Hammer.Backend do
  @moduledoc """
  The backend Behaviour module.
  """

  @type bucket_key :: {bucket :: integer, id :: String.t()}
  @type bucket_info ::
          {key :: bucket_key, count :: integer, created :: integer, updated :: integer}

  @callback count_hit(
              pid :: pid(),
              key :: bucket_key,
              now :: integer
            ) ::
              {:ok, count :: integer}
              | {:error, reason :: any}

  @callback count_hit(
              pid :: pid(),
              key :: bucket_key,
              now :: integer,
              increment :: integer
            ) ::
              {:ok, count :: integer}
              | {:error, reason :: any}

  @callback get_bucket(
              pid :: pid(),
              key :: bucket_key
            ) ::
              {:ok, info :: bucket_info}
              | {:ok, nil}
              | {:error, reason :: any}

  @callback delete_buckets(
              pid :: pid(),
              id :: String.t()
            ) ::
              {:ok, count_deleted :: integer}
              | {:error, reason :: any}
end